Core centralizer for permanent molds



CORE CENTRALI ZER O OOO OOOOOOOOOOOOO W I a June 1-5 1926. v 7 1,588,596

- H. 5. LEE

CORE CENTRALIZER FOR PERMANENT MOLDS Filed Jan. 8, 1925 2 Sheets-Sheet 2 v I INVENTOR.

742/7 0'- ,Zee

A TTORNEY.

Patented June 15, 1926 UNITED STA HARRY s. 113E101? PLYMOUTH, MICHIGAN.

CORE CENTM ZEB I 3 LEBMANE T hyp enated ia uaxy s, 1925 $er al no. 1, 68.

This invention relates to permanent molds, especially molds invented for casting ferrous articles, Molds of this kind expand under relatively great heat, and itis the object of the present invention to provide means which will properly center the core in such a mold.

In the drawings:

Fig. l is a vertical section of the mold and the core.

v Fig. 2 is a cross section on the line 22 of Fig. 1.

Fig. 3 is a plan View of a modified form. Fig. 4 is a fragmentary vertical section of the same.

Fig. 5 is a detail of one of the pins.

Permanent molds constructed ofmetal in casting ferrous materials become very hot and expand a few thousandths of an inch; hence the core which is fitted into and held in the mold by the walls of the same will not be accurately centered after the mold becomesheated up. It is, therefore, the object of the present invention to provide a compensating means which will secure ac.- curate casting by properly centering the mold.

In the drawings, I have shown a mold and a core such as would be suitable for casting a piston, but, obviously, other forms of casting could be easily adapted to carry out the invention here described. The mold is made in two sections, a and 6. Either one or the other of these sections can be withdrawn to permit of the insertion of' the core 0. This corehas a supporting head in the form of two annular ribs, d and e, which are fitted on to the seats h and z, or on the other hand, it may be said that the core head has an annular groove 7 into which fits the internal rib g of the mold. It 'does not matter just how this support is affected; suffice it to say that the upper part of the mold and the core have interlocking projecting and grooved parts, so that after the core has been fitted into one half of the mold the other half of the mold may be put in place, thereby forming a suitable suspension for the core in the mold.

However, when the molten metal is poured into the mold it greatly raises the temperature of the mold, and consequently in accordance with a familiar law the mold expands. It thereby draws away fromthe contacting surfaces of the'core. This permits the core to shift slightly in the mold,

lock nuts 77?. and applying a screw driver to the slotted end n of the stud.

It will, therefore, be apparent that as the mold heats up the studs may be released and adjusted to compensate for the expansion of the mold. When the desired adjustmentis secured this may be fixed by again tightening. the jamb nuts.

This is a o esirable form of adjustment, especially, where the temperature of the mold remains substantially constant during the pouring operations, as it is possible by releasing the lock nuts and adjusting the studs to get a fairly accurate centering of the core and to keep such an adjustment during the entire pouring operations. p

In Figs. 3, 4 and 5 I have shown a slight modification of this arrangement wherein tapered pins are used in place of the studs running 'directly through the side. By this arrangement the adjusting stud is brought on to the top of the mold where it is some what easier to operate. Furthermore, it is possible by using a relatively steep taper on the two pins, to reduce the movement of the spacing pin as regards the movement of the adjusting stud so as to get even a finer adjustment than is possible with the stud shown in Figs. 1 and 2.

What I claim is:

1. In a permanent mold, the combination of a plurality of metal mold sections that expand when heated, a core, the core and mold sections provided with inter engaging surfaces to support the core in the mold, and means for centralizing the core and the mold when the mold sections expand due to the heat.

2. In a permanent mold, the combination of a plurality of expansible metal mold sections, a core, the core and the mold sections provided with inter-engaging surfaces to support the core in the mold, and adjustable means carried by said expansible mold sections which may be given a permanent adjustment to compensate for the expansion of the mold sections so as to hold the core in a centralized position.

3. In a permanent mold, the combination of a plurality of expansihle metal mol'd sec: tions, a core, the core and the mold sections provided with inter-engaging surfaces for ing the expansion of the mold.-

4. In a permanent mold, the combination of a plurality of expansible mold sections, 7

a core, the core and the mold sections provided with inter-engaging portions for suspending the core in the mold in spaced relation with the walls of the mold and permanently adjustable spacing members properly centralizing the core notwithstanding the expansion of the mold sect-ions.

Intestimony whereof I have affixed my signature.

HARRY s. LEE.

for r 

